In construction applications, electrical devices such as switches and plug outlets are mounted within boxes which themselves are retained within walls, floors and ceilings with power supply conduits supplied to the box and to the electrical device contained therein. Outlet boxes are also used for mounting other devices such as communication cabling including optical communication, co-axial cables, twisted pair of cables and the like. Furthermore, outlet boxes can also be used to contain various valve and control devices such as in hospitals where various gases such as oxygen can be supplied in wall or in floor applications. Vacuum supply can also be provided to such outlet boxes. In typical construction applications, walls, floors, ceilings and the like are formed from a number of individual joists, studs, and rafters. Covering material is applied over the studs, joists and rafters with such covering materials including a wide variety of materials such as drywall, plywood, tile backing board, tiles, marble, lathe and plaster, stucco and a variety of other materials. The ultimate thickness of such materials applied onto studs, joists and rafters is not always known at the time the outlet boxes are mounted to the studs, joists, and rafters. In residential construction, outlet boxes are typically mounted such that the open mouth rim of the outlet box will be flush with the anticipated covering material. For example, when half-inch thick drywall is applied to studs, the outlet boxes will be installed such that they extend about one-half inch beyond the face of the studs, and when 1.6 cm (⅝-inch) thick drywall is installed, the boxes would be installed about 1.6 cm (⅝-inch) extending from the face of the studs. Thereafter, when the drywall is installed, a hole will be cut in the drywall to permit the box to project therethrough and remain flush with the outer surface of the drywall. Of course, if the builder decides to install a thicker wall covering material or apply additional layers of material after the conduit boxes are installed, the builder may need to first remove the wall covering material to expose the outlet boxes, reposition the outlet boxes and reapply the wall covering material.
In commercial and industrial construction, drywall rings are more typically used to set the distance to which the box extends outwardly from the studs. These drywall rings are usually attached with screws to the open front of the conduit box and can be selected as to the appropriate extension. These drywall rings have a rim portion that will lie behind the wall covering material once installed and an extension portion that extends through the hole formed in the wall covering material. Drywall rings provide a better interface between the conduit box and the hole made in the covering material. However, this can be a big problem because once the wall material is covered over the conduit box, it is typically not possible to replace the dry wall ring without breaking away the covering material, e.g. if the builder or someone who comes back decides to later apply an extra layer of material.
It would accordingly be desirable to have position adjustable outlet box system that permits a user to adjust the degree to which an outlet box projects even after the outlet box is installed and covered with wall facing materials.